A string of deaths in a hospital here has sparked fears of a potent, mosquito-borne disease and led authorities to seek a doctor’s arrest for allegedly sowing panic, leaving residents wondering how to explain their symptoms.

Angel Sarmiento, president of the College of Doctors in Aragua state, told reporters on Sept. 11 that a virus or bacteria may have been responsible for the deaths of eight patients in quick succession at the Central Hospital of Maracay. A ninth patient died three days after Dr. Sarmiento’s comments.

Insisting there was no cause for general alarm, President Nicolás Maduro last week accused Dr. Sarmiento of “psychological terrorism.”

The confusion in Maracay over the deaths—and over who to believe on their cause—shows how difficult it has become to arrive at a rational approach to public health in Venezuela. Part of the problem, doctors here say, is that the silencing of independent media has squelched the flow of information.

“To dissent, to have a position different from the government, leads to a witch hunt,” Dr. Sarmiento said in a telephone interview on Friday. “I am not a terrorist. I am a doctor.” He said he was still in Venezuela but was in hiding because he worried he would face a politically motivated prosecution.

Much of the fear has been focused on Chikungunya, a viral disease transmitted by mosquito bites that has been present in Africa and Asia for decades but only recently spread to the Americas. Though there is no cure for the disease, its symptoms can be alleviated with medication. The disease has killed at least 113 people this year in the Caribbean region, according to the Pan American Health Organization, with the islands of Martinique and Guadaloupe hardest hit.